1. Field of the Invention
The present invention relates to a touch screen panel used as a data input/output means of an electrical device. More particularly, the present invention relates to a touch screen panel in which a control unit for touch screen control is directly mounted on a sensor surface to improve touch sensitivity as well as preventing a touch fault.
2. Description of the Related Art
A variety of electronic devices employ an input unit for data input and an output unit for data output. A key button unit or the like is a representative example of the input unit. A display unit including a Liquid Crystal Display (LCD) module is a representative example of the output unit.
A touch screen panel capable of performing data input/output at the same position has recently been launched to diversify a function of the electronic device while significantly reducing a volume of the electronic device. The touch screen panel has a transparent touch panel disposed above the LCD module to simultaneously perform data input and output. There are various types of touch panels, such as a resistive touch panel, a capacitive touch panel, an ultrasonic wave touch type panel, an optical (infrared) sensor type touch panel, an electromagnetic induction type touch panel, etc.
Among the aforementioned touch panels, the capacitive touch panel includes a window portion made of a dielectric material, a dielectric layer (e.g., an Indium Tin Oxide (ITO) film layer and an ITO glass layer) bonded below the window portion and made of a Polyethylene Terephthalate (PET) or glass material, a conductive material coating layer which is disposed above the dielectric layer and of which a portion for touch sensing is coated with a transparent conductive material such as ITO, and an Optical Clear Adhesive (OCA) for bonding the ITO layer and the window portion. The conductive material coating layer includes a silver paste electrode portion. A Flexible Printed Circuit (FPC) is electrically connected to the electrode portion. A control unit for touch screen control is mounted on the FPC. An end portion of the FPC on which the control unit is mounted is electronically connected to a main board of the device.
However, when the control unit for touch sensing is mounted on the FPC as described above, the control unit may experience a contact fault due to flexibility of the FPC. As a result, touch sensitivity deteriorates, which leads to deterioration in reliability of the device.